Georgia 1.NR.2

1.NR.2 is a Georgia mathematics standard. These are the expectations under it.

• 1.NR.2.1

  Use a variety of strategies to solve addition and subtraction problems within 20.

• 1.NR.2.2

  Use pictures, drawings, and equations to develop strategies for addition and subtraction within 20 by exploring strings of related problems.

• 1.NR.2.3

  Recognize the inverse relationship between subtraction and addition within 20 and use this inverse relationship to solve authentic problems.

• 1.NR.2.4

  Fluently add and subtract within 10 using a variety of strategies.

• 1.NR.2.5

  Use the meaning of the equal sign to determine whether equations involving addition and subtraction are true or false.

• 1.NR.2.6

  Determine the unknown whole number in an addition or subtraction equation relating to three whole numbers.

• 1.NR.2.7

  Apply properties of operations as strategies to solve addition and subtraction problem situations within 20.

01

What Students Need to Do

Students connect addition and subtraction by showing how one operation can undo the other. They solve real-life problems within 20 and explain their strategy. They use known facts and operation properties to work efficiently.

02

What Mastery Looks Like

Students solve story problems within 20 using drawings, objects, equations, or mental strategies. They connect addition facts to related subtraction facts. They explain strategies such as changing addend order, making ten, or adding zero.

03

Common Misconceptions

Students may treat addition and subtraction as unrelated procedures. They may reverse subtraction facts because addition can be reversed. Some choose an operation from a keyword without considering the situation.

04

How to Assess It

Give this exit ticket: “Lena has 8 red cubes and 6 blue cubes. Find the total, write a related subtraction equation, and explain why 6 + 8 has the same total.”

1. 01

   Give pairs 13 counters, have them split the set, then record two addition equations and two subtraction equations.

2. 02

   Ask, “How can knowing 9 + 6 help you solve 15 − 9?” and have students explain with pictures and words.

3. 03

   Play fact-family match with cards showing an addition equation, a related subtraction equation, and a matching picture.

4. 04

   Set up a class store where students add item quantities and subtract sold items, keeping every total within 20.

• K.NR.5

  Explain the concepts of addition, subtraction, and equality and use these concepts to solve real-life problems within 10.